feat: improve app ui and project metadata

apps/api/ww_api/schemas/projects.py

@@ -6,6 +6,7 @@ snake_case；前端经 OpenAPI 生成 TS 类型消费。改字段 → 前端必
 from __future__ import annotations
 
 import uuid
+from datetime import datetime
 from typing import Any, Literal
 
 from pydantic import BaseModel, Field
@@ -34,6 +35,8 @@ class ProjectResponse(BaseModel):
     theme: str | None = None
     selling_points: list[str] = Field(default_factory=list)
     structure: str | None = None
+    updated_at: datetime | None = Field(default=None, description="项目最近更新时间")
+    pending_review_count: int = Field(default=0, ge=0, description="待审稿章节数")
 
 
 class ProjectListResponse(BaseModel):